I'm a little unsure of which filter option is best for primarily outdoor, daylight filming in situations where bright sunlight creates hot spots and harsh shadows. Can somebody explain the best application for ND vs. Polarizing filters?

Michael

Neutral density filters apply a calibrated reduction in light. Their darkness is calibrated (ex: ND 6, ND 4, etc.). Reducing the brightness through the lens will enable you to open the iris and get more detail in shade and shaadow areas. Note that it will also affect your depth of focus, although not dramatically for consumer and prosumer cameras.

Polarizing filters are designed to reduce, and in many cases eliminate, glare from polarized light sources such as reflections. They collaterally have the effect of improving color saturation in many daylight scenes. Polarizers will darken your exposure, somewhat like a neutral density filter, but that is not their primary function.

Both deserve investment for outdoor shooting. If your camera is not equipped with a built-in ND filter I would invest in this first, as it provides the typical videographer a bit more flexibility shooting in bright outdoor conditions.

For video camera use a linear polarizor will do just fine. Spend the money you save on a better quality linear. A linear is almost half the price of a circular.

Remember all glass is not created equally and you do geyt what you pay for.

Tiffen (ok)
http://www.tiffen.com/Header_page_tiffen_filters.htm

Hoya (ok)
http://www.thkphoto.com/catalog/hoya.html

B+W (the very best)
http://www.schneideroptics.com/filters/filters_for_motion_picture_&_broadcast_television/

Heliopan (the very best)
http://www.hpmarketingcorp.com/heliopan.html

Some cameras have neutral density filters built in.

Both filters can be of value, as Ken and Bryan describe, but neither will eliminate harsh shadows caused by shooting in direct sunlight, or lower contrast from bright sunlight versus shade. You must improve the shooting environment in these situations by various methods, such as using a "silk" over your subject to eliminate the harsh shadows caused by the overhead sunlight. (If you do this, you must have a background value that compliments your subject, or it will be overexposed) Or, add a reflector to bounce sunlight into your subject to wash out the shadows (which can result in squinting). Or, move your location. There is no "magic bullet" that can solve these problems.

Additionally, be aware when using a polarizer that if you need to pan your camera your exposure can change dramatically, as the effect of the filter changes in relation to the angle to the sun.

Polarizers and ND filters effect your exposure. They reduce the amount of light hitting the CCD. This can have a direct effect on the DOF. In no way do they effect contrast. The balance between highlights and shadows need to be balanced by other means. Do as Wayne suggests or use a graduated filter to balance between sky and foreground or highlights and shadows.

This is a limited use situation, but it may come in handy: if you are shooting a locked-off shot that has a serious contrast issue such as backlit (sun in front of you) vista, and the action takes place below the horizon line i.e. not in front of the sky, you can bracket your exposures and do a post fix. In other words, lock your tripod and head firmly and shoot the action with the exposure set for the actors (allowing the sky to blow out), then shoot a second pass with the lens stopped down for a nice exposure on the sky. Then it's just a matter of cutting a matte between the two in your editing software. As Wayne mentioned, an ND grad will do a similar effect but if you don't have access to that or a mattebox to use it in, this may work for you.

A specialized filter that can be helpful in high contrast situation is the Tiffen Ultra-Con series, but they are a bit tricky to work with & require some testing.

Michael

I gather you have acquired a pdx10?

On a bright sunny day in Texas a polarizer and ND8 will put you at f5.6

If you need slim DOF you will need an extra ND8 which will put you at f2.0

so 1 pol plus 2 x ND8 is recommended for flexibility

problem is the pdx10 allows only one 37mm filter behind the lens shade - if you are stacking more than one filter the shade will have to be removed.

The remedy I use on my 950 is as follows

1 get a 37mm to 49mm step ring
2 get all your filters in the 49mm size

when stacked the nature of this set up creates a lens shade through the stacked filters and thus will avoid any vignette problems when you shoot at the wide setting - especially important for the pdx10 16:9 mode

hope this helps

Great info, guys. This helps a ton.

Jay, you are correct that I bought a PDX10. The step ring is a great idea. I already have a set of filters for my 35mm cam that are 49mm, so that would allow me to make use of some of those filters.

Unfortunately, I'm limited in how much I can control the lighting or the "actors", since the actors are typically wildlife in a hunting situation. I can, however, control my setup in relation to the lighting source (sun) in most situations.

Thanks again for the great responses. I don't know if I've mentioned it before, but THIS SITE ROCKS! :)

Michael

I haven't been able to find an ND8 filter, but did find a couple of ND2's. I'm not sure what the relationship between the two numbers is. Can somebody give me a crash course?

Michael

Michael,
Schneider Optics, one of the best manufacturers of filters and accessory lenses, has a very good summary of this on their site (http://www.schneideroptics.com/filters/filters_for_motion_picture_&_broadcast_television/neutral_density_filters/).

How do I tell if the filter I have, which is identified on the ring as ND2 is the ND 2.0, which is 10 stops, or more likely ND + 2 (two stops?), which according to the chart would be ND .6, right?

It's a Quantary (made by Hoya) that I picked up at the local Ritz, because I couldn't find anything else locally in 37mm, or even a step ring. I'm assuming the ND2 (10 stops) is probably more of a specialty filter, and would be very dense?

Michael

You probably have the 0.2 -- the 2.0 is very dark and not something that you're likely to find in stock at most camera stores.

I am looking at getting some ND and Polarizer filters.

I am looking at some tiffen's
.3 , .6, .9 Which will be a good one for an outside wedding in a garden? Maybe all of them?

I assume a linear polarized lens?

I don't understand the numbering on filters. Sorry to be so green.

Mark

Marc,
Re: ND filters, selection partly depends on whether or not your camera's lens already provides one (or more) built-in ND filters (such as the GL2 and some of the XL1S lenses). Since all cameras can generally handle bright sunlight conditions it will also depend on how you think you want to manage your image via your iris. Darker image = wider iris (for a given shutter speed) = slightly shallower depth of field.

A linear polarizer is generally recommended for video cameras, although a circular will also work.

Mark:

The standard measure for ND filters is that a ND .3 equals one stop of light reduction, and thus a .6 is 2 stops and so on. This will be acurate for filters made by professional manufacturers such as Tiffen, B&W/Schneider etc. On this page (http://www.schneideroptics.com/filters/filters_for_motion_picture_&_broadcast_television/neutral_density_filters/) is a chart (scroll down) that lists the strengths and transmission of the ND series.

Avoid cheap ND filters (Quantaray etc.) because they may give your video an unusual color tint (they aren’t very neutral). There are several threads here about this effect.

I use circular polarizers for my video work. They are not that much more than linear polarizers and have the added benefit of doing double duty on your 35mm SLR (almost all modern cameras require circular polarizers). The use of circular polarizers on video cameras is somewhat controversial and has been discussed here in depth. Use the Search function if you want more information on the subject.

I am a little surprised at the recomendation for linear polarizers for an auto-focus system, whether still photographic or video. Linear polarizers and circular polarizers are not the same. Using a linear polarizer on an autofocus system can not only affect the autofocus system, but also the metering system.

It is a known fact to filter manufacturers, and we always tried to educate dealers on the differences. This said, you can use a linear polarizer on an autofocus system, however, there is no guarantee. The bottom line has been, if you use linear on an auto-system you run the risk of affecting the auto-focus and metering systems of your cam and while you can't necessarily predict WHEN this will happen to you, or if you are ever in a certain situation that may increase your risk, you WILL then lose your shot, and in some instances, shots are not re-creatable. This is usually why amatuers who are more concerned with cost than with quality and reliability buy linear and take the risks, pro's buy circular since they can't afford to lose an important shot due to trying to work "on the cheap".

Linear polarizer dusturbs mostly SLR TTL focusing that use microprizms or similar stuff for focusing.
Most videocams use more simple contrast-detection AF systems. I do not see how they can be affected by linear polarizer.
Did you see any videocam suffering from it? What brand?

I think it's more of a case that people aren't sure and recomend the circular just to be safe.

Linear polarizers and circular polarizers handle light differently. I haven't tested it on video cameras, however, I can tell you two things, first, as I mentioned, you CAN use linear with auto-focus systems, BUT the results are not guaranteed and in different circumstances people may get different results - in other words...your mileage may vary...and pro's can't afford to take chances. Secondly, as I also mentioned, it is not just auto-focus that can be affected, but the metering system as well.

<<you CAN use linear with auto-focus systems, BUT the results are not guaranteed ...and pro's can't afford to take chances.>>

This may be obvious but as a rule, "pros" don't use auto-focus.

I have personally never experienced metering problems using a linear pola on a broadcast video camera.

Well that's fine. Aside from the fact that every pro I ever met uses circular, and every dealer I ever dealt with agrees, as do the filter manufacturers themselves and camera manufacturers. Suffice it to say, to each his own, good luck and enjoy.

Then I'd say you just met your first pro who doesn't use one.

All the best,

David, I think you don't realise that "autofocus" (and other "metering" concepts in video) are in no way related to the systems used in some photographic camera's. If there are reasons for using circulars in video, it's for shure not the autofucus...which is involved.

Pro's don't use auto-focus.